1. Field of the Invention
The present invention relates to an apparatus for fabricating a flat panel display device, and more particularly, to an apparatus for fabricating a flat panel display device and method thereof. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for forming a transparent thin film or pattern with precise thickness and width by reducing a defective rate in the course of fabricating the flat panel display device.
2. Discussion of the Related Art
Recently, light and thin flat panel displays are mainly used as image displays for personal computers, mobile terminals, monitors of various information devices and the like. This flat panel display may include one of a liquid crystal display (LCD), a light emitting display, a plasma display panel, a field emission display and the like.
In particular, an organic field light emitting device is mainly used as the light emitting display. In this case, the organic field light emitting device consists of a 1st electrode, a 2nd electrode and an organic thin film layer between the 1st and 2nd electrodes. This light emitting display displays an image by controlling a light emission quantity of the organic light emitting devices.
In case of the liquid crystal display, a liquid crystal display panel consisting of a pair of substrates attached together with a predetermined space in-between and a liquid crystal layer injected between the pair of the substrates. In this case, a plurality of pixel regions are defined as a matrix type by gate lines and data lines. By adjusting a light transmissive rate through each of the pixel regions, an image may be displayed.
In order to fabricate the above-mentioned flat panel display devices, it is necessary to form metal thin films, which include various patterns, electrodes and the like, on at least one substrate. In particular, the various patterns, electrode, metal films and the like are formed by photolithography.
The photolithography consists of the processes for cleaning a substrate, forming a photoresist or various conductive metal layers on the cleaned substrate, exposing the photoresist or the conductive metal layer using a photo mask, developing the exposed photoresist or metal layer and the like.
However, according to the related art photolithography, it is difficult to adjust an exposure quantity in forming a transparent electrode or film having a high light transmissive rate. For instance, when a thin film or pattern is formed of such a transparent conductive metal as ITO (indium tin oxide), IZO (indium zinc oxide), AXO (Al-doped zinc oxide) and the like, a light applied to the substrate passes through the transparent metal layer and the substrate, reflects from an exposure device, and is then applied back to the substrate and the transparent metal layer. Therefore, it is difficult to control the exposure quantity. Thus, according to the related art, a limitation is put on precisely fabricating a transparent pattern or electrode by reducing a thickness or width of the transparent pattern or electrode. And, the related art photolithography has a high defective rate and a lower process efficiency.